Art of dentistry



jm.. 28, 3936. H. sPlRo ART 0F DENTISTRY Filed June l5, 1933 4 Sheets-Sheet l ART OF DENTISTRY Filed June 15, 1953 4 Sheets-Sheet 3 far? jf Jam., 28, 11936., H 5pm@ 2,29,3

ART oF DENTISTRY Filed June 15, 1955 4 Sheets-Sheet 4 ,1V/, J2 l L? ,yf/19A? riginal/,ra-

?atented Jan. 28, 1936 if' ED STATES .PATENT OFFICE 6 Claims.

This invention relatesto improvements in the art of dentistry and applies, more especially, to dental bridge construction, the methods and steps practiced in the making of bridges and articulators used ior this purpose.

Among the features of my invention is the provision of an articulator having two trays for supporting both a functional bite cast and a centric bite cast.

1U There are also numerous improvements in the construction and operation of my new articulator that will become apparent as I proceed with my specification.

Another feature of my invention is the making of a functional bite cast and using the same for forming the bridge. In this manner a bridge can be constructed completely in the laboratory before being placed in a patients mouth. Heretofore, bridges ordinarily have been formed with respect to a centric bite only in the laboratory; and then had to be reshaped or altered in the patients mouth in order to adapt the same to a functional bite. By making a functional bite cast and a centric bite cast, the bridge can be entirely completed in the laboratory. My'improved articulator is adapted to support these casts so that the same may be employed in making the bridge.

Other features and advantages of my invention will appear more fully as I proceed with my specication.

In the accompanying drawings I have shown my improved articulator and illustrated the various aspects of my invention. As shown in these drawings- Figure 1 is a top plan View of the articulator; Fig. 2 is a view in side elevation; Fig. 3 is a view taken as indicated by the line 3 of Fig. 2; Fig. 4 is a view ytaken as indicated by the line 4 of io Fig. 2; Fig. 5 is a vertical sectional view; Fig. 6 is a View showing a centric bite on wax; Fig. 7 is a view taken as indicated by the line 1 of Fig. 6; Fig. 8 is a view showing a centric bite cast in place on the articulator; Fig. 9 is a view of a functional a.; bite in wax; Fig. l0 is` a view taken as indicated by the. line IIJ oi Fig. 9; Fig. 11 is a view of the functional bite cast on the articulator; Fig. 12 is a view showing a step in the making of the bridge; Fig. 13 is a View taken as indicated by 5U the line I3 of Fig. 12; Fig. 14 is a view similar to Fig. 11 showing the bridge more nearly formed; Fig. 15 is a View in front elevation of the wax impression from which the bridge is formed; Fig. 16 is a bottom view of the same; and Fig. 17 is a view oi the bridge substantially completed.

As shown in the drawings, I indicates a rectangular base provided with a supporting post I2 at one end, said post having a head I2a countersunk in the base I3. On the post I2 is a sleeve I I held in position by the set screw I la. The post 5 I2 is provided with a keyway I2b and the sleeve I I is provided with a pin IId extending into this keyway to prevent rotation of the sleeve I I on the post I 2.

The upper end I2c of the sleeve I I has pivotally lo mounted thereon the centric bite tray I3. This pivotal mounting is accomplished by providing a collar I4 and bifurcating the end of the tray I3 to provide the two arms I31, I3a which embrace the collar I4. A pivot pin I5 fastens the collar 15 I4 to the par-t I2C and also pivotally supports the tray I3 by extending through the arms I3a, I3a. The collar I4 is provided with an extension I 4a adapted to be engaged by the lower end of the adjusting screw I6 in the tray I3 to limit the 20 downward movement of this tray.

Below the collar I4 there is provided another collar i1 having a pair of forwardly extending arms I la, I'Ia between which is rotatably supported by the pin I6 the functional bite tray 2|. 25 The member Il is provided with a pin 23 projecting into a socket in the upper end of the sleeve II to prevent horizontal swinging of the tray 2|, except when the member I 'I is lifted enough to remove the pin 23 from the socket. 30 23 indicates a spiral spring between the collars I 4 and II yieldingly holding the latter down, on the top of the sleeve II. 25 indicates a stop to limit the downward movement of the tray 2|.

The base I 0 is provided at its end oppo- 35 site the post I 2 with a standard 26, the upper surface of which is suitably marked, as indicated by 2'I, to make an impression in the cast carried by either of the trays. Such impression may be used in cooperation with the part 26 thereafter 40 to insure proper registry and placing of the casts on the articulator.

In Fig. 5 I have shown a master cast 30 in place on the base. In making this cast, a pair of properly spaced dowels 3! are east in the 45 same. These dowels have projecting pins 32 with undercut portions 33. Suitable holes are provided in the base to receive the pins 32 and in said base there is also provided a sliding member 34 provided with keyhole slots 35. The slide 34 50 is placed in the position shown in Fig. 4 when the master cast with the dowels is placed in position on the base. It is then slid to the right to the position shown in Fig. 5, whereupon the keyhole slots engage in the undercuts 33 on the 55 dowels to lock the master cast rmly on the base I0. Y Y

Figures 6 and 7 are views of the mouth showing the taking of a centric bite in wax. In these views, the lower jaw or arch is indicated by lill,Y

it being understood that these views may represent anyrpart of either jaw or arch in which a bridge is to be installed. 4I and 42 may indicate the abutment teeth in the lower arch 46 which are to carry the bridge. The upper arch is indicated by 43 and 44, 66 indicate the teeth therein. In Figs. 6 and '7, 45 indicates a piece of wax in the patients mouth in which a centric bite is being made. By centric bite is meant a bite without any sliding or swinging movement of the jaws. After taking the bite as shown in Figs. 6 and 7, the wax impression thereof, as indicated by 45, is placed on the master cast 36 mounted on the articulator as shown in Fig. 8, and a centric bite cast i6 is made on the tray i3. The tray is provided with holes 13e to make an interlock with the plaster 46.

After the centric bite cast has been formed, a functional bite isk made in a similar manner. For example, as shown in Figs. 9 and 10, 5E) may indicate wax in which a functional bite is being made. That is, the jaws are brought together and then moved sidewaysV and swung back and forth relatively the same as wouldY occur in the operation of chewing or grinding food between the teeth of the two jaws. I have referred to this as a functional bite, meaning that the jaws are not merely7 brought together but that the teeth are slid back and forth sideways vand forwardly and backwardly to some extent in making the bite, as if food were being chewed'or ground. IThis wax impression 50 of a functional bite is then placed on the master cast in the articulator, as shown in Fig. 11, and a functional bite cast 5l is cast on the tray 2|, said tray likewise being provided with holes 2 la to form a plaster lock.

After the formation of the centric bite cast and functional bite cast, the bridge structure is built up 0n the' master cast with respect to said bite casts. For example, this may be done as illustratedl somewhat in Figs. 12 to 17, inclusive. As here shown, porcelain facings 6|] may be supported between the members Ma and 42a which are plaster models in the master cast of the abutment teeth 6i and 42. These facings #56, for

example, may be held in position by a plaster bringing the extension 2la of the cast into position on the top 21 of the standard 26. This will always determine the normal position of either bite cast with respect to the master cast 30. It will be seen, therefora'that the wax impression 62 may be built up with regard to both the functional bite cast and the centric bite case. When Y tional bite cast and the centric bitecast. When the wax impression has been completed, the same may be reproduced in permanent form in any suitable manner. For example, the bridge construction and support shown in my co-pending application, Serial No, 632,263, led September 8, 1932, may be utilized. In Fig. 17, purely by way of example, I have shown crowns 8| and 82 attached to the ends of the bridge for supporting the same in the mouth' on the abutment teeth 4I and 42. Y

While I have shown and described certain embodiments of my invention, it is to be understood that it is capablev of many modifications. Changes, therefore, in the 'construction and arrangement may be made without departing from the spirit and scope of the invention as disclosed in the appended claims, in which it is my intenf,

tion to claim all novelty inherent in my invention as broadly as permissible, in View of the prior art.

What I regard as new, and desire to secure by Letters Patent, is:

1. In an articulator adapted to support a cen- -f tric bite cast by means of a centric bite tray, a support for a master cast, and means for supporting a functional bite cast in normal position with respect to a master cast on said support.

2. An articulator as claimed in claim 1, in which the means for supporting the functional bite cast is swingably mounted on the articulator.

3. In an articulator adapted to support a centric bite cast by means of a centric bite tray; a base; means for supporting a master cast on the base; and a tray supported from said base, said tray adapted to carry a functional bite cast.

4. An articulator as claimed in claim 3, in which the tray supported from the base is swing- Vably mounted to swing in a horizontal plane.

5. In an articulator adapted to support a centric bite cast by means of a bite cast tray; a base adapted to support a masterrcast; a post on said base; a registry device on said base spaced from said post; and means on said post for supporting t a functional bitercast with a'portion of said cast in cooperation with said registry device.

6. In an articulator adapted to support aV centric bite cast by means of a centric bite tray;

a base adapted to support a master cast; a post on said base; and a functional bite cast tray car-y ried by said post, said tray being vertically and horizontally swingable on said post.V

HARRY SPIRO. 

